Ribbon mechanism for type-writing machines.



' PATENTED DEC. 10, 1907.

RIBBON MECHANISM FOR TYPE WRITINGVMAGHINES.

APPLIOATION FILED JUNE 1. 1904. RENEWED JAN. 4, 1907.

2 SHEETS-SHEET 1.

No. 873,244- PATENTED DEG. 10, 1907. J. W. KENNEDY. RIBBON MECHANISM FOR TYPE WRITING MACHINES.

APPLICATION FILED JUNE 1. 1904. RENEWED JAN. 4. 1907.

2 SHEETS-SHEET 2.

1 To all whom it may concern:

, mechanisms therefor.

' simple and durable ribbon mechanism-for typewriting machines, which will operate totion. Fig. 2 is a partial rear elevation there- "lever for disengaging the escapement rack bar; andlfig, 5 ma plan in the Patent Oliice onApril 2, 1904, Serial revolubly mounted on rods 9 and 10 secured in brackets '-11 at f chin'e frame.

subject of-the King of Great Britain, residing "at Chicago ,Gook county Illinois, have. inventvention consists of the various features, combinations-offeatures and details of construction heremafter described and claimed.

drawings, shown my improved. ribbon mechcompletedescription thereof. r I Referring now to the drawings, l-wlesiged frame, comprising end. pl ates 3 rigidly con- UNITED STATES J MEsw. KENNEDY; oF onlolie ,m-rmis, .rssIdNoR','BY its 7 .,KENNEDY TYPEWRITER T-IOh OF NEW YORK.

m sa MEonAmsMi oa 'rrrn-iwnr'rme Machines Ap'plicatimrfiled dime-1.1904, SerialNn. (210.758. Renewed Jannary-l. 1Q07. Serial Hm 3501822.

Be it known that I, J AMES'W. KENNEDY,

ed certain new and useful Improvements in Ribbon Mechanism for Type-Writing Machines, of which the following is a complete specification.

This 'nvention relates to typewriting machines and relates particularly to ribbon T The ooj ect of the invention is to provide a automatically reverse the ribbon feed when theribbon reaches the limit of movement "in either. direction. a

To, this end a ribbon mechanism of my in- In the'accompanying drawings, in which a ribbon 'Inec'hanism of my invention is fully illustrated,Figure-1 is a sectional side ele-- vation on the line 1-1 of Fig. 3 of a machine embodying a ribbon mechanism of my invenof. Fig. 3 is a sectional front elevation on the line3-3 of Fig. 1. Fig. 4 is a left hand side view of the platen carriage showing the view of the ribbon and ribbon guides.

' For purposes of illustration, I have, in the anisni as embodied in or applied to a vertical shownand described in ail-application for U. S Letters Patent heretofore filed by me No. 201,284, to which referenceis made for a hates the frame of the machine and 2 the platen thereof revolubly mountedin a-pivot nected by transverse rods 4, and 5 the baron which the platen carriage is supported.

The ribbon 6 is wound upon spools 7 and 8 opposite sides of the ma-.

ANYiQF Mil-mamas, or matter Specification of Letters Patent,

maintain'the pivot pin 17": normally .gagement with one orthe other-10f the-pivot I katentpd 7 and 8 so-as to rotatertherewith.are ratchet wheels 12, the teeth of which are adaptedto x; be engaged by the opposite endsof a pawl arm or rod 13 pivoted to a crankwarm 14secured toa shaft-15 revolubly mounted in'a suitable-bracket 16 onthe machine frame, the relation beingsuch that, when said pawl; arm 13 is engagement with the teeth-pf either of the ratchet wheels 12, it will: eidisengaged from the other 1 To provide for. maintaining .the pavvl arm 13 in normal engagement. with either of --the1 ratchet wheels 12-,as may be-desired,..said 7o pawl arm 13 is mounted upon the :cranle arm 14 by means of a piv t hiftableje gth of said-pawl arm and Spring orzspringsisor are applied to said pawl-arm insuch-mannerv that the tension of said spring; or springs will be varied as the pivotalpoint'sof said-@pawl arm is shifted, therelation beingsuchqthat, when at either limit of itsmovement, there will be anunbalanced spring tension' 'exented, on said pawl arm. which will move thesame pivotally. so that in one extreme position one endthereof will be thrown into engagement with'one of said ratchetzwheels and inithe other extreme position the opposite endtherew of will. be thrown into engagement .with the other ratchet wheel. I Inthe preferable. construction shown, a pivot pin 17-issecured in the crank arm 14 which extends thnough a longitudinal slot 18 in the pawl arm.1 3- and is adapted to engage-pivot bearings 19 and20 at the ends of said slot, a projection21ebeing formed on. theside of theslot :between sai pivot bearings .19' and 20. Secured in the pawl arm 13 directly'below the pivot bear.-;-

ings 19 and 20 are pins 22-, which'areconstrength. With this consti'uction it'gis-pbe vious that the-springs 24and25WilLQXert-an upward pull on'the pawl ,arm gl3 jgan d ill xenearings19 and 2Q. It is also obviousethan when saidpivot .pin is incngagemlent with 105, .one'of said pivot bearings, asfor examplejthe pivot bearing 19., thetensionfon the springlf24 will be decreased and-that saidgspringtwill Rotation is adapted to beimparted-to' ribbon spools 7 and 8 to feed the ribbon; the following manner :Secured to said spools exert a pull in a substantially straight line connecting the pins 17 and 23, while the tension on the spring will be increased and will-be applied to the pawl "arm 13 at a considerable distance from the pivot pin 17.

Said spring 25 will thus-exert an unbalanced pull on the pawl-arm 13 in a direction to move'the same pivotally to throw an end of said pawl arm into engagement with the ratchet wheel secured'to the ratchet wheel 8 the pawl arm 13 are wheels; 12 and insure engagement of said pawl arm with the teeth of said ratchet wheel 1n. the designed manner, As shown, said 3 gmdesconsist of'sheet metal clips 26 which are secured to the pawl arm by spring pressure, the web connecting the sides of said fchp' being cut away beyond the ends of said pawl arm. to provide for the passage of the ratchet wheels.

Reciprocating movement is imparted to the-pawl arm 13,'as the machine is operated, to cause it to engage the teeth of the ratchet wheels 12 in the following manner :Secured to the-rear end of the shaft 15 is a lever arm 27, the up er endof whichengages teeth 28, on a-rackar 29 on the platen carriage so as a0;

to be moved pivotally in one direction by the movement of said platen carriage under the .influence'of the main feed spring applied thereto, andIis adapted to be moved pivotally in the opposite direction, as-the teeth 28 connects. said lever arm, with a rigid support pass over the end of the leverarm 27 wherey said arm is released, by a spring 30, which as shown a post 31 on the machine frame.

Pivotal movement of said lever arm 27, un-

their the influence of the spring 30 is limited 'by a suitable stop. As shown, said lever In order that engagement of the lever arm,

arm extends through a slot 32 in the top of the machine frame, the end of which forms the stop which limits the pivotal movement thereof in the desired manner.

27 with the teeth 28 on the rack bar 29 may not interfere with retracting said rack bar and thus the platen carriage, a spring pawl 33 is pivoted to the end of said lever arm 27,

pivotal movementof which, under the in- .fluence of the mainspring, is limited by a suitable stop, said pawl beingfreely movable in the opposite direction. As shown, said pawl is formed of a piece-of sheet metal bent so'thatthe sides thereof will embrace the sides of the lever arm 27, the connecting web of which engages the rack teeth 28. As

shown, also, said pawl extends "below its point of ivotal attachment to the lever arm 27 and t e pivotal movement thereof, under the influence of the platen carriage, is limited by contact of its connecting web with the "ed 9. of said lever arm.

' J 11 order that the rack teeth 28 may be disstrike the same.

engaged from the lever arm 27, to provide for free movement of the platen carriage, transversely of the machine, the rack bar 29 is preferably pivoted to the platen carriage, a suitable spring maintaining said rack bar normally in operative position and said rack bar being adapted to be moved pivotally into disengaged position by a suitable lever.

In the preferable construction shown, the rack bar 29 is the rack bar of the escapemcnt, which controls thefeed of the platen carriage, said rack bar being pivoted to a rod 34 mounted in suitable bearings in the platen carriage, a coiled spring 35 operating to maintain said rack bar normally in operative position, which is defined'by the pinion 36 of the escapement. Pivotal movement to disengage the rack bar 29 is adapted to be imparted thereto by means of a lever 37, piv-- oted between its ends to one of the pivot rods of the platen-frame, the rear end of which is connected to the rear end of a bell lever 38, the front. end of which bears upon the top of the rack bar 29 in front of the pivotal point thereof. The front end of the lever 37 projects in front of the platen at the left side thereof in convenient positionto be enga 'ed by the thumb of the left hand while said hand is holding the carriage against too rapid movement under the influei'ice of the main carriage spring. A flat head screw 39 extends through a slot 40. in said lever and operates to guide said lever and prevents it from being bent-out of shape.

The machine shown in the drawings is of the type known as a visible writing machine, the type striking the frontof the platen so that the writing will always be exposed to the view of the operator. The ribbon 41 is wound upon the spools 7 and 8 and between said spools is confined in suitable guides which hold it in operative position in front .of the platen at the point where the type will In order that the ribbon may not obscure the writin it is supported normally below the writing ine andis raised each time an operating lever is depressed so as to bring said ribbon into position to be struck by the type.

In the preferable construction shown, the ribbon guides comprise guide rollers 42 revolubly mounted on the .-1nachine frame, stationary slotted guides 43 and a central ribbon bobber 4A. As shown, the ribbon spools 7 and 8 are a little in front of theribbon bobber 44' and the rollers 42 are set at a slight angle to ovefiome the side draft of said ribbon as it is drawn from one spool to the other.

The ribbon bobber 44 consists of a fiat piece of sheet metal which is vertically movable in a suitable guide bearing on the machine'frame, the ribbon 41 being confined between the rear face of said metal plate and pins 45 secured thereto, said pins 45 being the. type-'topa'ss said ribbon" bobber and strike'th'e platen or the ribbonWhic'h overlies tlievplaten. 1

10 Laterahdisplacem'entof the upper end of the -ribbon' bobber is prevented by means of lugs 47- thereon which embrace the edges of a ,ri 'd' type bfar guide 48 secured to the frame 0 the machine. As shown, said ribbon bobher is fitted to and is longitudinally movable in a' slot 49 formed in the face of a boss 50011 the'machine frame to which the hanger support 51" is secured, said hanger support 1 operating t'oclose the" open side-of said slot and to confine said'ribbo'n bobber'in the bearingformed thereby.

As-heretoforestated;the ribbon 41, carried 'byjtheribbon bobb'er44, is normally b'elowfthe ;.w'ri;ting line, so as to expose, the writingto the'view ofthe'operator, and is raised" by the bobber at, every-depressionof the o tween the platen and the ty .e. 1 Asshowinythe ribbon boh ber.44 'israised arid lowered in the following manner Pivo-ted to "a" bracket 52 jsecured to the platen shift bar 5 is'a bell lever 53," a slot 54 in one en'djofwhich enga es ap'in'55 securedin the low'er end of then bon bobber.

alink' 56; withfone arm'of afbelllever, 57 pivoted',to'a} bracket 58 secured in fixed position on'flth'e machine frame, the other arm ..45- that depressing any o f the operating-levers willdepiess: the bar 59,- which, through the bellflevers." 57 and 53, will operate to raise the ribbon bobber4'4 a desired distance. As sho'fw'tu the ,bell lever 57, instead of being ,50 connected directly with the bar -59 is connected directly 'to p the; pivoted escapement rema e. a

In ordefto secure a uniform operation of I framei fil which is.connectedto-said bar 59 5 5 the 'i'ilihfonbobbei '44'ihbothits normal and shifted positiolns, the relative ositions of the belllevers"53 and '57' are sue thattlie link, sstonne "ingth'em will extend at 's'ubstan j lr sa eang es bprosi i d s -a so unset righ ahgieswthqfsireai n gfmovei t tei t. 56 shag; th p at n s innfingeramnesiaare-microns;v i tli iibboiif ffed "isnesignewte be reversed automatically, when the ribbon. reaches the under the influence of the pawl arm 13, and

perating leve r g t ,libboli b h PP -35 site, end'ofsaid bell lev'erl53is connected by .arm which will become unbalanced-on oppop3 In altypewriting machine, therboriibiny, I tion with the ribbon spools and ratchet mpro e ribbon m ch s limit of its movement in either direction. As shown, this is effected in the following mannerz lvhen the ribbon is placed in themachine, the ends thereof are attached to the ribbon spools 7 and 8. Assume that] the pawl arm 13 is in engagement with the ratchet wheel 12 secured to the ribbon spool 7. As the machine is operated," said pawl arm will impart-step by step rotationto the I spool 7 in a direction to wind the ribbon thereupon and to reel it off from the spool 8 When the ribbon has been entirely unwound fromthe spool 8, the tension on said ribbon will prevent further rotation of the spool 7 will thus prevent movement of said pawl arin 1'3 with the arm 14 on the'rock shaft 15, which will operate to shift the pivot pin 17in said arm 14 from the pivot bearing 20 in said pawl arm to the pivot bearing 19, which will. operate to relieve said pivot arm 13 from the tension of the s ring 24, and will subject it to tension fronr the spring 25 on the opposite side of the pivot pin 17 at a distance there, from, which will operate to im art pivotal '90 movement to said pawl arm on t is pivot pin 17 to disengage it from the ratchet wheel 12 secured to the ribbon spool 7 and cause it to engage theratchet wheel secured tot he' spool8, thereby reversing the ribbon feed,in the manner desired' I claim as my invention 1. In a typewriting machine, the combina tion with the ribbon s ools and ratchet wheels secured torotate t erewith, of a pawl arm, a support movable transversely of the machine on which said pawl arm is pivoted by means of a shiftable pivbt bearing, means for exerting a, lateral tension on said pawl sitesides of its pivotal pointpas the pivot bearing of said pawl arm 1s 'shiftedand means for imparting movement to said movable, supportv transversely of the machine in bot'h; directions, substantially as described. I 2. In a ty ewriting machine, the combine: tion with the ribbon s ools and ratchet wheel's secured to rotate t erewith, ofaawlj arm, a support movabletransversely o the machine and means to impart movement thereto in both] directions, pivotal 'connec tion betweensaid pawl arm and said movable support compr sing a slot in one thereof and. a, ivot stud 1n the otherwhich extends throng 1 said slot and means for' exertinga lateral tension on said pawl arm which will become unbalanced on opposite sides of said pivot stud as said pivot stud moves lengthv Wise of the SlOl'1;lI1,S&lCl pawlarnn'substans tially as described. 125

machine to which said'nawl .arm'is pivoted 130,

by means of a shiftable pivotbearing, a

spring or springs which connect said movable support and sald pawl arm, the relation being such that said SPIlIl or springs will exert an unbalanced tension on saidpawl arm on opposite sides of its p vot hearing as said pivot bearing is -shifted,.and means to impart movement to said movable support transversely of the machine in both directions, substantially as described.

4. In a typewriting machine, the combination with the ribbon' spools and ratchet wheels secured to rotate therewith, of a pawl arm, a support movable transversely of the machine and means to impart movement thereto in both directions, pivotal contially as described.

5. In a t-ypewriting machine, the combination with the ribbon spools and ratchet wheels secured to rot ate therewith, of a pawl arm, a support movable transi'ersely of the machine and means for imparting movement thereto in both directions, pivotal connection between said pawl arm and said movable supportcomprising a pivot studin one thereof and a slot in the other through which said pivot stud extends, said slot being provided with pivot bearings located at a dis tance from each other and springs which connect said movable support and said pawl arm, said springs being connected to one thereof at a point between said pivot bearing and tothe other at points adjacent to said pivot bearings, substantially as described.

6. In a ty ewriting machine, the combination with t e ribbon s 001s and ratchet wheels secured to rotate t erewit-h, of a pawl arm, a support movable transversely of the machine and means for imparting movement thereto, in both directions, pivotal connection between said pawl arm and said movable support comprising a pivot stud in one thereof and a slot in the other through which said ivot stud extends, said slot being provided with pivot bearings located at a distance from each other and springs of substantially equal strength whic connect said movable support and said pawl arm, said springs being connected to one thereof at a point in line with said pivot stud and to the other at points adjacent tothe pivot bearings in said slot, substantially.asdescribed.

7. In a typewriting machine, the combination with the ribbon spools and ratchet wheels secured to rotate therewith, of a pawl arm, a support movable transversely of the of said pivot as said machine and means for imparting movement thereto in both directions, pivotal connection between said pawl 'arm and said movable support comprising a pivot stud in one thereof and a slot in the other through which said pivot stud extends, said slot being provided with pivot bearings located at a distance from each other, a projection on the side of said slot between said pivot bearin s and spring connection between said movab e support and said pawl arm whereby an unbalanced tension will be exerted on said pawl arm, on opposite sides of said pivot stud as said pivot stud is shifted from one pivot bearing to the other, substantially as detion between said pawl arm and said n1ovable support comprising a pivot stud in one thereof and a slot in the other through which said pivot stud extends, said slot being provided with pivot bearings located at a distance from each other, a projection on the side of said slot between said pivot bearings and springs of substantially equal strength which connect said movable support and said pawl arm, said springs being connected to one thereof at a oint in line with said pivot stud and to tfi jacent to the pivgt bearings in said slot, substantially as described.

9. In a typewriting machine, the combination with the ribbon spools and ratchet wheels secured to rotate therewith, of a awl arm, a rock shaft, an arm thereon to W 'ch said pawl arm is shiftable pivot, spring connection between said pawl arm and said arm on said rock shaft whereby an unbalanced'tension will be exerted on said pawl arm on op osite sides ivot is s 'fted, and means to im art oscillatory movement to said rock shat, substantiall as described.

10. In a t nation with t e ribbon spools and ratchet wheels secured to rotate therewith, of a awl' arm, a support movable transversely o the machine and means for imparting movement thereto in both directions, shiftable, pivotal connection between said pawl arm and said movable support and spring connection between said pawl arm and said movable support whereby an unbalanced tension will be -exerted on said pawl arm on opposite sides of said pivot bearing as such pivot bea is shifted and means to shift said pivot hearing when the ribbon reaches the limit of its moveme'ntin either direction, substantially as described.

11. In a typewriting machine, the combie other at points adpivoted by means of a ewriting mac e, the combination with the ribbon spools and ratchet wheels secured to rotate therewith, of a pawl arm, a support movable transversely of the machine and means to impart movement thereto in' bothdirections, shiftable pivotal connection between said pawl arm and said movable support, spring connection between said pawlarm and said movable support whereby an unbalanced tension will be exerted on said pawl arm on opposite sides of said pivot bearing as said pivot bearing is shifted and means controlled by the operation of the machine for shifting said pivot bearing when the ribbon reaches the limit of its movement in either direction, substantially as described. i

12. In a typewriting machine, the combination. with the ribbon spools, the ribbon wound thereon and having its ends attached thereto and ratchet wheels secured to rotate with said ribbon spools, of a pawl arm, a sup port movable transversely of the machine and means to im art movement theretoin both directions, s ftable pivotal connection between said pawl arm and said movable support and spring connection between said pawl arm and said movable supportv whereby an unbalanced tension. will be exerted upon said pawl arm on. opposite sides of said pivot bearing as said pivot bearing is shifted, substantially as described. i

13. In a typewriting machine, the combination with the ribbon spools, the ribbon -wound thereon and having its ends secured thereto and ratchet wheels secured to rotate with said ribbon spools, of a pawl arm, a rock shaft, an arm thereon to which said pawl arm is pivoted by means of a shiftable pivot, spring connection between said pawl arm and saidarm on said rock shaft whereby an unbalanced tension will be exerted on said pawl arm on opposite sides 'of said pivot )earing as saidpivot bearing is shifted and means to impart oscillatory movement to said rock shaft, substantially as described.

14. In a typewriting machine, the combi nation with the ribbon spools, the ribbon wound thereon and having itsends attached thereto and ratchet wheels secured to rotate with said ribbon spools, of a pawl arm, a rock shaft, an arm thereon, pivotal connection between said pawl arm and said arm on said rock shaft comprising a pivot stud in one thereof and a slot in the other through which said pivot stud extends, said slot being provided with'pivot hearings located at a distance from each'other, spring connection be tween said pawl and said rock arm whereby an unbalanced tension will be exerted on said pawl arm on opposite sidesjof said pivot stud as said pivot stud is shifted from one pivotlb'earing to the other and means to impart oscillatory movement to said rock shaft, substantially as described.

In a typewriting machine, the combination with the ribbon spools and ratchet wheels secured to rotate therewith, of a awl' arm, a rock shaft, an arm on saidrocks aft,=; a shiftable pivotal connectionbetween said pawl arm and said arm on said rock shaft, spring connection between said .pawltarm' and said arm on said rock shaft whereby an j unbalanced tension will be exerted on-saidpawl arm on opposite sides of its pivot bear- 1 ing as said pivot bearing is shifted; and I means to impart oscillatory movement tor said rock shaft, said means com rising' a lever arm secured thereto, a rac 'on: the platen carriage with which said lever arm engages whereby movement of said carriage; will rotate said rock shaft in one direction and a spring applied to said lever arm to rotate. said rock shaft in the opposite direction, substantially as described. I

16. In a typewriting-machine, the combination with ribbon spools and ratchet wheels 1 secured to rotate therewith, of a pawl arm, a

rock shaft, an arm on said rock shaft, shift: able. pivotal connection between said pawl arm and said arm on said rock shaft, s ring connection between said pawl arm an said arm on said rock shaft whereby an unbalanced tension will be exerted on said pawl arm on opposite sides of its pivot bearing as said pivot bearing is shifted, and means to impart oscillatory movement to said rock shaft, said means comprising a lever arm secured thereto, a rack on the platen carriage with which said lever arm enga es, whereby movement of said carriage wi rock shaftin one direction, a spring applied to said lever arm to rotate the same in the opposite direction, and a spring pawl, pivoted to the end'of said lever arm to ermit retraction of the platen carriage, su stantially as described. Y

rotate said,

17, In a typewriting machine, the combi,

nation with the ribbon spools andratchetwheels secured to rotate therewith, of a pawl arm, a rock shaft, anarm on said rock-- shaft, a shiftable pivotal connection between said pawl arm and said arm on said rock shaft, spring connection between said pawl arm and said arm on said rock shaft whereby; an unbalanced tension will be exerted on said pawl arm on opposite sides of its pivot bearingas said pivot bearing is shifted, and means to impart oscillatory movement to said rock shaft, said means comprising'a rack bar pivoted upon the platen carriage, teeth thereon with which said leverarm en'- gages, whereby movement of said-carriage will rotate said rock shaft in one direction, a spring applied to said lever arm to rotate said rock shaft in the opposite direction, and means to move said rack bar pivotally to disengage the teeth thereon from said lever arm, substantially as described.

18. In atypewriting machine,.the combination with the ribbon spools and ratchet wheels secured to rotate therewith, of a arm, a rock shaft, an arm on said rock 5 iaft,

a shiftable pivotal connection between saidpawl arm and said arm on said rock shaft,

the platen "oarrriage, teeth thereon was which said spring pawl engages, whereby movement of said carriage will rotate said rock shaft in'one direction, a spring applied to said lever arm to rotate said shaft in the opposite direction, and means to move said rack bar pivotally to disengage the teeth thereon from said lever arm, substantially as described.

19. In a typewriting machine, the combi nation with the ribbon spools and ratchet wheels secured to rotate therewith, of a pawl arm, arock shaft, an arm on said rock shaft, pivotal connection between said pawl arm and said arm on said.rock shaft comprising a pi ot stud in one thereof and a slot in the other through which said pivot stud extends, said slot being'provided with pivot bearings located at a distance from eachother, pring connection between said pawl arm and said arm on said rock shaft whereby an unbalanced tension will be eXerte (1 upon said pawl arm on opposite sides of said pivot stud as said' pivot stud is shifted from one pivot bearing to the other, and means to impart oscillatory movement to said rock shaft, said means comprising a lever arm secured thereto, a springpawl pivoted to the end of said lever arm, a rack bar pivoted upon the-platen carriage, teeth thereon with which the pawl on said lever arm engages,

whereby movement of said carriage will rotate said rock shaft in one direction, a spring applied to said lever arm to rotate the same in the opposite direction and means to move said rack bar pivotally to disengage the teeth thereon from said pawl on said lever arm, substantially as described.

20. In a tvpenriting machine, the combination with the ribbon spools, the ribbon wound thereon and having its ends attached thereto and ratchet wheels secured to rotate therewith, of a pawl arm, a rock shaft, an arm on said rock shaft, pivotal connection between said pawl arm and said arm on said rock shaft comprising a pivot stud in one thereof and a slot in the other provided with pivot bearings located at a distance from each other, spring connection between said pawl arm and said. arm on said rock shaft whereby an unbalanced tension will be exerted on said pawl arm on opposite sides of said pivot stud as said pivot stud is shifted from one pivot bearing to the other, and means to impart oscillatory movomen t to said rock shaft, saidmeans comprising a lever arm secured thereto, a spring pawl pivoted to said lever arm, a rack bar pivoted to the platen carriage, teeth thereon with which said pawl on said lever arm engages, whereby movement of said carriage will rotate said rock shaft in one direction, a spring applied to said lever arm to-rotate said rock shaft in the opposite direction, and means to move said rack bar pivotally to disengage the teeth thereon from said lever arm, substantially as described.

In testimony, that I claim the foregoing as my invention, I affix my signature in presence of two subscribing witnesses, this 26th day of May, A. D. 1904.

JAMES IV. KENNEDY.

\Vitnesses K. A. CosTELLo, B. MoL'rER. 

